Airbag modules with airbags or gas bags effectively protect motor-vehicle occupants during a collision. During a collision, a gas generator releases pressurized gas into the airbag to inflate the same (which is typically located in a steering wheel, dashboard, side door, or seat) within a short time. In addition to the airbag and the gas generator, the airbag module also contains a number of other components, such as a housing containing or housing the airbag in a folded state, a cover for the housing, and a gas generator support for holding the gas generator. Additional components, such as retaining rings are also used to fasten the airbag.
U.S. Pat. No. 5,797,622 discloses an airbag module having a two-part housing mounted on a steering wheel. The housing has a housing lower part, which is formed integrally on the steering wheel, and an upper part serving as the cover, with a hollow-cylindrical holding device fastened to the upper part for holding a cylindrical gas generator. The folded airbag is placed over the outer surface of the holding device.
European patent publication EP 0 622 276 A1 discloses an airbag restraint system for vehicles. Here, a preassembled airbag is fastened to a securing plate and then is inserted together with the securing plate into the interior of a cover of the restraint system. The cover is assigned, as a lower part, a generator support in the form of a supporting plate on which a gas generator is secured.
To save costs and to simplify the installation of the airbag module and the mounting to a part of the motor vehicle, it is desirable to reduce the number of the individual parts of an airbag module. In this respect, European patent publication EP 0 832 791 A2 describes an airbag module for a vehicle-occupant restraint system having an airbag, a gas generator, and installation screws having a fastening extension that projects away from the airbag module for fastening the gas-bag module to a vehicle part. The screws have a locating head. The edge of the blow-in opening of the airbag is clamped between the locating head and a nut screwed onto the stem of the installation screw. Furthermore, a retaining ring is positioned in the interior of the airbag and an installation plate is provided for the gas generator. The blow-in opening edge is sandwiched between the retaining ring and the installation plate. This module has a cover with a downwardly extending side walls that extend to the screws, which hold the cover. This design reduces the number of components. Nonetheless, to securely fasten the airbag to the gas generator, this airbag module requires, in addition to the housing cover, further components are needed, namely the installation plate on the gas generator and the retaining ring.
There is still a need to further reduce the number of airbag module components. The present invention addresses this need.
The present invention relates to an airbag module, an airbag thereof, and a method of mounting the airbag to the module.
One aspect of the present invention relates to an airbag, which can include an airbag mount for mounting the gas generator to the airbag. The mount can include a slot for inserting the gas generator into the airbag, and a plurality of passages for receiving fasteners for securing the airbag module. The slot can form at least two mounting zones, where the passages are located. The mounting zones can be configured to partially overlap when the fasteners are inserted through the passages.
The airbag mount can further include a cutout for passage of an ignition cable. The cutout can be formed between the overlapping zones. The slot can form an even number of the mounting zones, and can be cross shaped for forming four mount zones. Each zone can have one of the passages, which can be punched holes, each with a reinforced edge.
Another aspect of the present invention relates to an airbag module, which can include the airbag described above. The module can include a single-piece housing having a cover and a generator support, the airbag, which is folded and positioned inside the housing, and a gas generator connected to the generator support. The generator support can be foldably or pivotally connected to the cover.
Part of the gas generator can rest on the generator support, which can be hingedly connected to the cover. Specifically, the support can be hinged to the cover using at least one film hinge. The generator support can comprise at least one foldable tab hingedly connected to the cover. The entire housing can be made of plastic, in particular by injection molding.
The generator support can comprise one to four tabs. For two ore more tabs, they can be configured to partially overlap each other. The housing can include latches for securing the tabs to the cover.
The gas generator can include a flange for securing the gas generator to the generator support. The flange can further include fasteners for connecting the airbag module to a steering wheel, or any other part of a vehicle. The fasteners can be threaded bolts for example.
The airbag can be fixed directly to the gas generator, for instance, by sandwiching the airbag between the generator support and the gas generator.
Another aspect of the present invention relates to a method of mounting the airbag of the airbag module. The method can comprise providing the airbag with the slot, which forms at least two mounting zones, and the passages in the two mounting zones, providing the single-piece housing having the cover and the generator support foldably connected to the cover. The generator support can have openings for passage of the fasteners. The method can further include positioning the folded airbag inside the cover, providing the gas generator with the fasteners, and inserting the gas generator into the airbag through the slot. The method can further include inserting the fasteners through the passages and partially overlapping the two mounting zones, and folding the generator support onto the gas generator positioned inside the cover and inserting the fasteners through the openings.